1. Field of the Invention
The present invention relates generally to tillage tools and, more specifically, to a standard assembly with a knock-on sweep and structure for preventing the sweep from falling off the shank.
2. Related Art
Standard assemblies for implements such as chisel plows and field cultivators typically include an upright shank pivotally connected at its upper end to a frame bracket and extending downwardly to a tool-receiving end which mounts a shovel or sweep. Previously available mounting structure included bolts extending through aligned holes in the tool and the shank to secure the tool. When the tool in such an assembly has to be replaced because of wear or damage, the bolts must be removed. Wear and corrosion of the bolts substantially hinders removal and often makes the replacement a difficult and time-consuming task.
Several solutions to the problem of easily and quickly replacing worn elements such as sweeps on shanks have been developed over the years, including the use of a tapered adapter brackets fastened to the end of a standard and providing a self-locking fit with a matching taper on the sweeps. However, such devices have suffered from one or more problems, including need for additional parts and the loss of sweeps during transport if the tapers on the adapters and sweeps do not match correctly or if the tool is not mounted with sufficient force. In an attempt to try to avoid the problem of sweeps falling off the shanks in quick mount arrangements, some manufacturers have offered a retaining clip in the form of a sheet metal stamping with a spherical protrusion that fits into a hole in the sweep. However, the clip increases cost and the required number of parts, and an incorrect taper in either the shank adaptor or the sweep can prevent the protrusion from engaging the hole in the sweep to render the clip ineffective. Further, many of the tapered adaptor assemblies do not permit easy changeover to a conventional two-bolt mounting, an option that some farmers wish to have readily available to assure a very sound mounting under certain conditions where a knock-on type of arrangement is inappropriate.
In many of the shank assemblies that have a quick attaching feature for mounting a tool on a shank, a relatively wide profile is presented along the shank and at the mounting location. Such a profile often results in unwanted residue disturbance and higher draft loads.